1. Field of the Invention
The invention relates to electronic data storage and retrieval systems, particularly to magnetic recording systems.
2. Description of the Background Art
Magnetic recording systems are used widely for storing (i.e., writing) and retrieving (i.e., reading) digital or analog data signals to and from magnetic media, such as disks, tapes, drums, and the like. In the course of magnetic recording, however, signal asymmetry may arise when an initial, written signal does not remain substantially the same or "symmetric" to such written signal, when such written signal is read subsequently. Typically, because of non-uniformities or premagnetization in the magnetic media and/or the recording heads, undesirable signal asymmetry may result.
Conventionally to eliminate signal asymmetry from recording systems, a test signal is recorded in magnetic media, and based on a subsequent reading of the recorded test signal, a manual adjustment is made to the recording head circuitry to compensate for any detected signal asymmetry. The conventional approach, however, is manually tedious and does not adjust asymmetry in response to asymmetry arising subsequently to initial manual adjustment. Accordingly, there is a need for an improved technique for adjusting asymmetric recording signals.